I have defined my route in a separate route.js file as below (details removed for brevity)
var express = require('express');
var router = express.Router();
router.route('')put(function(req, res){
console.log(req.params.id); //prints undefined
});
and in server.js I map this route as below
var route = require('./routes/route.js');
app.use('/api/use/:id/role', route);
My route function is correctly invoked but the id parameter is not available in the router handler. Am I doing anything wrong?
Use the mergeParams option:
var router = express.Router({ mergeParams : true });
Full standalone example:
var express = require('express');
var app = express();
var server = app.listen(3000);
var router = express.Router({ mergeParams : true });
router.route('').get(function(req, res) {
console.log('id', req.params.id);
return res.sendStatus(200);
});
app.use('/api/use/:id/role', router);
Related
I'm trying to set up a simple express project, and backend will be purely for api and frontend will be vue. I tried adding an api router, and not only does it not work, but even the root page doesn't work. I've not coded in express for a very long time, and wondering if some one could guide me on what's the problem? The error message is 404 NotFoundError: Not Found.
I'm navigating to localhost:3000, and I can see the call on the terminal, so port should be correct too?
/src/api/urls.js
var express = require('express');
var router = express.Router();
router.get('/', function(req, res) {
res.send('Just a test');
});
module.exports = router;
I didn't change the folder structure/naming for the original routes/index.js.
/src/routes/index.js
var express = require('express');
var router = express.Router();
router.get('/', function(req, res) {
res.send('Just a test');
});
module.exports = router;
And for the main file
/src/app.js
var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var logger = require('morgan');
var indexRouter = require('./routes/index');
var apiRouter = require('./api/urls');
var app = express();
app.use(require('connect-history-api-fallback')());
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');
app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use('/', indexRouter);
app.use('/api', apiRouter);
// catch 404 and forward to error handler
app.use(function(req, res, next) {
next(createError(404));
});
// error handler
app.use(function(err, req, res, next) {
// set locals, only providing error in development
res.locals.message = err.message;
res.locals.error = req.app.get('env') === 'development' ? err : {};
// render the error page
res.status(err.status || 500);
res.render('error');
});
module.exports = app;
All good except endpoint url that should be with middleware function only. Modifying these should work,
/src/api/urls.js
var express = require('express');
var router = express.Router();
router.get('/api/test', function(req, res) {
res.send('Just a test');
});
module.exports = router;
/src/routes/index.js
var express = require('express');
var router = express.Router();
router.get('/api/test2', function(req, res) {
res.send('Just a test');
});
module.exports = router;
In app.js you should register your routes as,
// Routes
app.use([
require('./src/api/urls'),
require('./src/routes/index'),
]);
Access by url ( http://<yourhost>/api/test1 )
app.js :
var index = require('./routes/index2');
var users = require('./routes/users');
app.use('/', index);
app.use('/users', users);
index2.js :
var express = require('express');
var router = express.Router();
/* GET users listing. */
router.get('/', function(req, res, next) {
res.send('respond with a resource');
});
when I go to localhost:3000/ I don't see the text in send function
I guess your browser is you waiting for a response?
If you change index2.js to be a function and return the router, you'll be adding it as a middleware with app.use('url', middleware). I hope this helps
app.js
var index = require('./routes/index2');
var users = require('./routes/users');
app.use('/', index()); //Invoke the object to get the router back
app.use('/users', users);
index2.js
var express = require('express');
var router = express.Router();
module.exports = function() {
/* GET users listing. */
router.get('/', function(req, res, next) {
res.send('respond with a resource');
});
return router;
};
Returning the router from index2 to be used as a middleware
I want to access a param defined in my app.use (index.js) inside my app.get (idCtrl.js). Below I have an boiled down version of my code. The route works and sends me to the controller for a url such as /1234 but I can't access :id from req.params.
index.js
var express = require('express');
var app = express();
var idCtrl = require('./idCtrl');
...
app.use('/:id([0-9]{4})', idCtrl);
idCtrl.js
var express = require('express');
var router = express.Router();
...
router.get('/', function(req, res){
// I wanna access :id from the app.use in index.js
});
...
The proper way to handle that situation is
First, set up your param
router.param('id',function(req,res,next,id)
{
//d owhatever you want with your param here
req.paramID = id; // save it in your req
next(); // Continue to your get('/:id')
};
Then, set up the route using the param
router.get('/:id', function(req, res){
console.log(req.paramID); // You got your param here
});
Here is my routes/users.js file:
var express = require('express');
var router = express.Router();
/*
* GET userlist.
*/
router.get('/userlist', function(req, res) {
var db = req.db;
var collection = db.get('userlist');
collection.find({},{},function(e,docs){
res.json(docs);
});
});
module.exports = router;
In this code, what is the req object? And when we call req.db... that's made available to us via this right in app.js:
var mongo = require('mongodb');
var monk = require('monk');
var db = monk('localhost:27017/nodetest2');
var routes = require('./routes/index');
var users = require('./routes/users');
var app = express();
app.use(function(req,res,next){
req.db = db;
next();
});
What is the app.use exactly doing here?
I'm trying to create a really simple node API using express.js 4 but I need a few 'realtime' events for which I added socket.io. I'm fairly new to both so I'm likely missing something basic but I can't find good docs/tuts on this.
In the express app (created with the express generator) I have something like this based on simple examples and project docs that I read. This works OK and from client apps, I can send/receive the socket events:
var express = require('express');
var path = require('path');
var logger = require('morgan');
var api = require('./routes/api');
var app = express();
var io = require('socket.io').listen(app.listen(3000));
app.use(logger('dev'));
app.use(express.static(path.join(__dirname, 'public')));
app.use('/api', api);
io.sockets.on('connection', function (socket) {
console.log('client connect');
socket.on('echo', function (data) {
io.sockets.emit('message', data);
});
});
// error handlers omitted
module.exports = app;
but I want to use the sockets from my API routes (in the ./routes/api.js file that I 'require' above). For example, someone might use the API to PUT/POST a resource and I want that broadcast to connected socket.io clients.
I cannot see how to use the 'io' variable or organise the code currently in the io.sockets.on('connection' ... function inside express routes. Here's the ./routes/api.js file:
var express = require('express');
var router = express.Router();
var io = ???;
router.put('/foo', function(req, res) {
/*
do stuff to update the foo resource
...
*/
// now broadcast the updated foo..
io.sockets.emit('update', foo); // how?
});
module.exports = router;
One option is to pass it in to req object.
app.js:
var express = require('express');
var path = require('path');
var logger = require('morgan');
var api = require('./routes/api');
var app = express();
var io = require('socket.io').listen(app.listen(3000));
app.use(logger('dev'));
app.use(express.static(path.join(__dirname, 'public')));
io.sockets.on('connection', function (socket) {
console.log('client connect');
socket.on('echo', function (data) {
io.sockets.emit('message', data);
});
});
// Make io accessible to our router
app.use(function(req,res,next){
req.io = io;
next();
});
app.use('/api', api);
// error handlers omitted
module.exports = app;
./routes/api.js:
var express = require('express');
var router = express.Router();
router.put('/foo', function(req, res) {
/*
do stuff to update the foo resource
...
*/
// now broadcast the updated foo..
req.io.sockets.emit('update', foo);
});
module.exports = router;
I've modified your files a little bit, may you check if it works?
You can pass the io you've defined to your routes like below;
require('./routes/api')(app,io);
I didn't test the Socket.IO parts but there is no syntax error and routes also working.
server.js file:
var express = require('express');
var app = express();
var path = require('path');
var logger = require('morgan');
var io = require('socket.io').listen(app.listen(3000));
app.use(logger('dev'));
app.use(express.static(path.join(__dirname, 'public')));
io.sockets.on('connection', function (socket) {
console.log('client connect');
socket.on('echo', function (data) {
io.sockets.emit('message', data);
});
});
require('./routes/api')(app,io);
console.log("Server listening at port 3000");
api.js:
module.exports = function(app,io) {
app.put('/foo', function(req, res) {
/*
do stuff to update the foo resource
...
*/
// now broadcast the updated foo..
console.log("PUT OK!");
io.sockets.emit('update'); // how?
res.json({result: "update sent over IO"});
});
}
Supposing you want to access the SocketIO from anywhere in your application, not just in the router, you could create a singleton for it. This is what works for me:
//socket-singletion.js
var socket = require('socket.io');
var SocketSingleton = (function() {
this.io = null;
this.configure = function(server) {
this.io = socket(server);
}
return this;
})();
module.exports = SocketSingleton;
Then, you need to configure it using your server:
//server config file
var SocketSingleton = require('./socket-singleton');
var http = require('http');
var server = http.createServer(app);
SocketSingleton.configure(server); // <--here
server.listen('3000');
Finally, use it wherever you want:
//router/index.js
var express = require('express');
var router = express.Router();
var SocketSingleton = require('../socket-singleton');
/* GET home page. */
router.get('/', function(req, res, next) {
setTimeout(function(){
SocketSingleton.io.emit('news', {msg: 'success!'});
}, 3000);
res.render('index', { title: 'Express' });
});
module.exports = router;
One more option is to use req.app.
app.js
const express = require('express');
const path = require('path');
const logger = require('morgan');
const api = require('./routes/api');
const app = express();
const io = require('socket.io').listen(app.listen(3000));
// Keep the io instance
app.io = io;
app.use(logger('dev'));
app.use(express.static(path.join(__dirname, 'public')));
// ...
app.use('/api', api);
module.exports = app;
routes/api.js
const express = require('express');
const router = express.Router();
router.put('/foo', function(req, res) {
/*
* API
*/
// Broadcast the updated foo..
req.app.io.sockets.emit('update', foo);
});
module.exports = router;
Refactored Edudjr's answer.
Change the singleton to create a new instance of socket.io server
const { Server } = require('socket.io');
const singleton = (() => {
this.configure = (server) => this.io = new Server(server)
return this
})();
module.exports = singleton
Initialise your express app, the server and the singleton.
// initialise app
const app = express();
const server = require('http').createServer(app);
// configure socket.io
socket.configure(server)
Then in your router
const socket = require('/utils/socket-singleton');
socket.io.emit('event', {message: 'your message here'})
I think best way is to set io as a property of req, like below:
app.use(function(req,res,next){
req.io = io;
next();
});
app.use('/your-sub-link', your-router);